Atom-Light Elementary Excitations in a Periodic Ensemble of Ultracold Atoms
Résumé
We derive the excitation spectrum for light coupled to atoms in an optical lattice, close to a 0 to 1 atomic transition, for the branches that are mainly of atomic nature. We explicitly include the quantum atomic motion, which leads to remarkable features such as a finite lifetime of the elementary excitations and their energy dependence with the lattice depth, that will show up in a real experiment as we discuss. It also makes the theory naturally divergence-free and resolves a controversy for the occurrence of a spectral gap.
Domaines
Autre [cond-mat.other]
Origine : Fichiers produits par l'(les) auteur(s)